黄土地区隧道初期支护衬砌结构形式研究

发布时间：2019-06-13 10:53

【摘要】：在国家西部大开发战略政策的驱动下,我国西部公路、铁路、高铁等交通基础设施建设持续蓬勃发展。我国西部以山地、盆地为主的地形特点,决定了施工设计中较大的隧道比例,研究适用于西部黄土地区隧道的施工结构及工法,特别是研究初期支护衬砌结构和施工工法显得极为必要。本文通过对黄土地区湿陷性、地应力重分部快、易崩溃、节理发育不规则等地质特点的分析研究;对黄土地区隧道初期衬砌易开裂、施工过程沉陷大且不均匀、衬砌后易出现空洞等易发病害成因的分析研究;对目前广泛应用的新奥法中喷锚初期支护衬砌喷射混凝土与黄土密贴性差、初期承载力小、掌支面安全风险大、喷射混凝土回弹量大、施工进尺小等工艺适用性的分析研究,针对喷锚初期支护衬砌结构在黄土区隧道施工、运营中的缺陷,设计出采用模筑混凝土、钢拱架、锚杆结构联合支护的一次模筑初期支护衬砌结构形式。从施工安全、运营安全、经济效益、工程质量、施工进度等方面,比选了传统的喷锚混凝土初期支护衬砌与一次模筑混凝土初期支护衬砌两种工法的在黄土地区施工的优缺点及适用性,并对一次模筑初期支护衬砌工法的设计理念、结构形式、工艺过程、黄土区适用性进行了阐述,总结出一次模筑初期支护衬砌在黄土区隧道应用的优势。尤其是重点阐述了一次模筑衬砌台车的设计应用,确保了施工安全、加快了施工进度,进一步体现出一次模筑初期支护衬砌结构形式的优势。建议推广一次模筑初期支护衬砌结构形式应用于软弱石质围岩、特殊地质区五级以上围岩、溶洞陷穴发育地区的地下隐蔽工程施工。
[Abstract]:Driven by the strategic policy of western development, the construction of transportation infrastructure, such as highway, railway, high-speed rail and so on, continues to flourish in western China. The topographic characteristics of mountainous areas and basins in western China determine the proportion of tunnels in construction design. It is very necessary to study the construction structure and construction method suitable for tunnel in western loess area, especially the initial supporting lining structure and construction method. In this paper, the geological characteristics of collapsibility, fast ground stress, easy collapse and irregular joint development in loess area are analyzed and studied, and the causes of prone diseases, such as cracking of tunnel lining in initial stage, large and uneven settlement in construction process and voids after lining, are analyzed and studied. Based on the analysis and study of the technical applicability of shotcrete and anchor initial support lining shotcrete and loess, such as low initial bearing capacity, large safety risk of palm support surface, large springback amount of shotcrete, small construction scale and so on, aiming at the defects of shotcrete and anchor initial support lining structure in tunnel construction and operation in loess area, the formwork concrete and steel arch frame are designed in view of the defects of shotcrete and anchor initial support lining structure in tunnel construction and operation in loess area. The form of lining structure in the initial stage of bolt structure combined support. From the aspects of construction safety, operation safety, economic benefit, engineering quality and construction progress, the advantages, disadvantages and applicability of the traditional shotcrete anchor concrete initial support lining and the primary formwork concrete initial support lining in loess area are compared, and the design concept, structure form, technological process and applicability of the primary formwork initial support lining method are expounded. The advantages of supporting lining in loess tunnel in the initial stage of primary formwork are summarized. In particular, the design and application of primary formwork lining trolley are expounded, which ensures the construction safety, speeds up the construction progress, and further reflects the advantages of the initial supporting lining structure form of primary formwork. It is suggested that the form of supporting lining structure in the initial stage of primary formwork should be applied to the construction of underground concealment engineering in the areas of weak stone surrounding rock, special geological area and above grade 5 surrounding rock, and the development of caverns.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U455.91

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